Answer: B) 11 Explanation: Half the Product of Number in the upper & lower box gives the number in the middle box. i.e. 18 x 4/2 = 36 15 x 6/2 = 45 In the same way  8 x N/2 = 44 => N = 11.

Answer: C) 9 : 10 Explanation: The ratio of X and Y ages at present is 4:5.  Then, the ratio 20 years ago will not be more than the ratio at present. So, from the options 9:10 is not satifying => its ratio is 0.9 which is greater than presnt ratio of 0.8.

Answer: B) Africa Explanation: We know that, there are 7 continents in the world. They are : Asia, Africa, Australia, North America, South America, Europe and Antarctica.   Africa - 53 countries Asia - 48 countries Europe - 45 countries Antarctica - 0 countries   Hence, the continent Africa has most number of countries with 53 countries and in second place Asia has 48 , third Europe has 45 countries.